Incidence and clinical significance of myocardial bridging with ECG-gated 16-row MDCT coronary angiography

Aims The aims of this study were to evaluate the incidence and the clinical significance of myocardial bridging in 401 patients with chest pain examined with 16-row Multidetector CT (MDCT) coronary angiography. Material and methods Four hundred nine consecutive patients who had chest pain or symptoms suggestive of coronary artery disease were involved in this study. Patients with heart rates ≥65 beats/min received 25–50 mg of atenolol orally 1 h before the scan. CT coronary angiography was performed with a 16-row MDCT scanner. CT coronary angiographic images were evaluated by consensus of two radiologists, who were blinded to clinical information. Clinical correlation was made between the presence and type of myocardial bridging on MDCT and the clinical results based on history, examination, and any subsequent clinical workup at the 2-month follow-up by a consensus of two physicians. Results Among the 401 patients, 23 (5.7%) cases of myocardial bridging were detected. Twenty-one (5.2%) cases of myocardial bridging were located at the middle third of the left anterior descending coronary artery (LAD), one (0.25%) case was at the proximal third of the LAD, and one (0.25%) case was at the distal third of the LAD. Superficial bridging was identified in 15 patients and deep bridging in 8. The length of tunneled artery was between 5 and 27 mm, with a mean of 15.7 mm, and the depth of tunneled artery was between 1.0 and 7.0 mm, with a mean of 3.2 mm. Out of four patients whose chest pain was assumed to be associated with myocardial bridging, three patients had deep bridging. In the other 19 patients with bridging, alternative causes of chest pain were present. Conclusions We found the incidence of myocardial bridging in this patient group to be 5.7%. Larger multicenter studies are required to evaluate the incidence of myocardial bridging and to determine a link between myocardial bridging and chest pain.